load_app: Load a web app defined by a gWidgetsWWW2 script

In jverzani/gWidgetsWWW2: Toolkit implementation of the gWidgets API for use with web pages

Description

There are two basic tasks that gWidgetsWWW2 does: a) create the javascript to populate a page (or part of the page) and b) create a means for AJAX requests between the web browser and the R process. For b) there isn't much to say except that it is supposed to just work.

Usage

load_app(script_name, app_name = NULL, port = NULL,
  session_manager = make_session_manager(), open_page = TRUE,
  show.log = FALSE, ...)

Arguments

script_name	path to gWidgetsWWW2 script
app_name	base name for script, unique per project. Derived from script name if not specified.
port	Initial port for Rhttpd server, provided it hasn't already started.
session_manager	an instance of make_session_manager
open_page	logical. If TRUE call browseURL to open the app.
show.log	If TRUE, logged information is written to the console.
...	Passed to WebPage object. Named arguments body and head can be used to insert information into each, such as loading of style sheets etc. through head. One can also subclass WebPage and pass this in via webpage.

Details

As for a) there are things one can pay attention to. The simplest case is really pretty simple. Write some script, save it to a file and call this function with the script name (and path if needed). This simple case will create a full screen app. Each app runs in its own environment in the R session, so running lots of instances can be expensive. That is, don't expect gWidgetsWWW2 to scale.

To embed an app within a web page, use an iframe tag.

Examples

## open an app that takes the entire page
gw_script <-  system.file("examples/ex-hello-world.R", package="gWidgetsWWW2")
if(interactive()) load_app(gw_script, "HelloApp")

jverzani/gWidgetsWWW2 documentation built on Feb. 9, 2020, 5:18 p.m.